Positioning of drills and other machinery in an underground environment, such as in mining, is often challenging. Precision and accuracy are often required when positioning and carrying out drilling processes, in order to reduce costs and danger, to operators, crew and machinery.
One method of mining is known as drift mining, in which longitudinal tunnels are drilled into hard rock underground. The tunnel may be created by tunnel boring machines, which grind away at the face of the tunnel until the desired tunnel is formed. Alternatively, the tunnel may be created by blasting. This involves drilling blastholes into the face to a known depth, filling the blastholes with explosives and creating the tunnel by detonating the explosives. In the blasting method, the positioning of the end locations, or “toes” of the blastholes affects how cleanly the tunnel is excavated. Even positioning of the toes helps to ensure that the tunnel is excavated with little or no remaining debris or “bootleg”. The presence of bootleg in a newly excavated tunnel may be dangerous and may be time-consuming and/or costly to remove, typically costing about $3000-$4000 per foot. However, positioning of the toes is often challenging since the blastholes typically are drilled 10-15 ft deep into the face and only 2-3 inches in diameter, with the result that a skew of as little as 1 degree during drilling can result in significant error in positioning of a toe.
In the blasting method, typically a drill machine referred to as a jumbo is used. The jumbo drill includes booms with drills mounted at the end. These booms are maneuvered to position and orient the drills for creating the blastholes in the rock. The positioning and orientation of the booms may directly affect the accuracy of the positioning of the toes. Most conventional jumbo drills typically rely on the judgment of the operator to place the drills and drill the blastholes accurately based on visual observation of the booms from the cab of the drill machine. The operator typically marks the drill face with paint and uses his subjective judgment to attempt to get the booms positioned and oriented to correctly place the resulting toes. There are typically no optical, video or visual guidance or feedback provided to the operator to assist in this process. The result is typically inconsistent toe placement, and an average of 5% bootleg is typically present in the excavated tunnel.
A small number of conventional jumbo drills may use a series of cables to measure distance traveled by the boom, and may also use gyros and accelerometers mounted on the drill slide to generate the same data for the operator. Such machines may also automate the process of drilling to reduce the reliance on the operator and to improve the accuracy of the process. However, such machines are often cost-prohibitive and unreliable. For example, such machines may be vulnerable to the hazards of the environment, such as moisture, temperature and vibration. Such machines often require extensive maintenance, are often complex and expensive to maintain, and often require long down-times for maintenance.
It would be useful to provide a solution for measuring and capturing the motion of machinery and other processes in an underground environment, to provide feedback to an operator. It would be useful to provide a solution that may be retrofitted to conventional jumbo drills or other machinery or apparatus. I would also be useful to provide a system that would require little maintenance.